Sessions at PyCon US 2012 about IPython on Wednesday 7th March

IPython provides tools for interactive and parallel computing that are widely used in scientific computing, but can benefit any Python developer. We will show how to use IPython in different ways, as: an interactive shell, an embedded shell, a graphical console, a network-aware VM in GUIs, a web-based notebook with code, graphics and rich HTML, and a high-level framework for parallel computing.

IPython started as a better interactive Python interpreter in 2001, but over the last decade it has grown into a rich and powerful set of interlocking tools aimed at maximizing developer productivity with Python while using the language interactively.

Today, IPython consists of a kernel that executes the user code and controls the user's namespace, and a collection of tools to control this kernel either in-process or out-of-process thanks to a well-specified communications protocol implemented over ZeroMQ. The kernel can do much more than execute user code, including introspection of objects in the user's namespace, detailed error reporting with rich tracebacks, history logging of inputs and outputs with an SQLite backend, a user-extensible system of commands for interactive control that don't collide with user variables, and much more.
Our communications architecture allows these same features to be accessed via a variety of clients, each providing unique functionality tuned to a specific use case. We expose a number of directly usable applications:

An interactive, terminal-based shell with many capabilities far beyond the default Python interactive interpreter (this is the default application opened by the ipython command that most users are familiar with).

A Qt console that provides the look and feel of a terminal, but adds support for inline figures, graphical calltips, a persistent session that can survive crashes (even segfaults) of the kernel process, and more. A user-based review of some of these features can be found here.

A web-based notebook that can execute code and also contain rich text and figures, mathematical equations and arbitrary HTML. This notebook controls the same kernel as the other two applications, but instead of offering a linear, terminal-like workflow, it presents a document-like view with cells where code is executed but that can be edited in-place, reordered, mixed with explanatory text and figures, etc. This model is a kind of literate programming environment popular in scientific computing and pioneered by the Mathematica system, that allows for the creation of rich documents that combine computational experimentation and results with other explanatory elements. A detailed review of this system can be found here.

A high-performance, low-latency system for parallel computing that supports the control of a cluster of IPython engines communicating over ZeroMQ, with optimizations that minimize unnecessary copying of large objects (especially numpy arrays). These engines can be controlled interactively while developing and doing exploratory work, or can run in batch mode either on a local machine or in a large cluster/supercomputing environment via a batch scheduler.

In this hands-on, in-depth tutorial, we will briefly describe IPython's architecture and will then show how to use and configure each of the above components. We will also discuss how to use the underlying IPython libraries in your own application to provide interactive control.

The tutorial will give a hands-on introduction to manipulating and analyzing large and small structured data sets in Python using the pandas library. While the focus will be on learning the nuts and bolts of the library's features, I also aim to demonstrate a different way of thinking regarding structuring data in memory for manipulation and analysis.

The tutorial will teach the mechanics of the most important features of pandas. It will be focused on the nuts and bolts of the two main data structures, Series (1D) and DataFrame (2D), as they relate to a variety of common data handling problems in Python. The tutorial will be supplemented by a collection of scripts and example data sets for the users to run while following along with the material. As such a significant part of the tutorial will be spend doing interactive data exploration and working examples from within the IPython console.

The tutorial will also teach participants best practices for structuring data in memory and the do's and don'ts of high performance computing with large data sets in Python. For participants who have never used IPython, this will also provide a gentle introduction to interactive scientific computing with IPython.